anyType is a basic type from http://www.w3.org/2001/XMLSchema.xsd that is not included in the built-in Tersus package XML/www.w3.org/2001/XMLSchema.
This is something that should be fixed, but as a quick patch please try to use XMLSchema.trp as a replacement for the XMLSchema package.
To do so:
If it works properly, we'll include the updated package in the next release.
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